UPDATE: Attorney: Miss. man denies mailing suspected ricin

This undated photo obtained from the facebook page of Paul Kevin Curtis, shows, according to neighbors, Paul Kevin Curtis, 45. Curtis was arrested Wednesday, April 17, 2013, at his home in Corinth, near the Tennessee state line. He is accused of mailing letters with suspected ricin to to national leaders.

AP Photo

By ADRIAN SAINZ and HOLBROOK MOHR - Associated Press

Published: Thursday, April 18, 2013 at 01:35 PM.

Updated at 2:15 p.m.

OXFORD, Miss. (AP) — A Mississippi man charged with mailing letters with suspected ricin to national leaders was surprised by his arrest and maintains he is innocent, his attorney said Thursday after his first appearance.

Paul Kevin Curtis, 45, wore shackles and a Johnny Cash T-shirt in the federal courtroom. His handcuffs were taken off for the brief hearing, and he said little.

He faces two charges on accusations of threatening President Barack Obama and others.

He nodded his head and said, "Yes, ma'am" when the judge asked whether he understood the charges and possible penalties

He did not enter a plea on the two charges. The judge said a preliminary hearing and a detention hearing are scheduled for 3 p.m. Friday.

Attorney Christi R. McCoy said Curtis "maintains 100 percent that he did not do this."

"I know Kevin, I know his family," she said. "This is a huge shock."

McCoy said she has not yet decided whether to seek a hearing to determine if Curtis is mentally competent to stand trial.

Curtis, who was arrested Wednesday at his home in Corinth, near the Tennessee state line, was being held in the Lafayette County jail in Oxford, Miss.

An FBI affidavit says Curtis sent three letters with suspected ricin to President Barack Obama, U.S. Sen. Roger Wicker and a Mississippi judge. The letters read:

"No one wanted to listen to me before. There are still 'Missing Pieces.' Maybe I have your attention now even if that means someone must die. This must stop. To see a wrong and not expose it, is to become a silent partner to its continuance. I am KC and I approve this message."

The affidavit says Curtis had sent letters to Wicker's office several times before with the message "this is Kevin Curtis and I approve this message."

In several letters to Wicker and other officials, Curtis said he was writing a novel about black market body parts called "Missing Pieces."

Curtis also had posted language similar to the letters on his Facebook page, the affidavit says.

The documents indicate Curtis had been distrustful of the government for years. In 2007, Curtis' ex-wife called police in Booneville, Miss., to report that her husband was extremely delusional, anti-government and felt the government was spying on him with drones.

Curtis was arrested Wednesday at his home in Corinth, near the Tennessee state line. He was being held in the Lafayette County jail in Oxford, Miss.

He believed he had uncovered a conspiracy to sell human body parts on the black market and claimed "various parties within the government" were trying to ruin his reputation.

Curtis had been living in Corinth, a city of about 14,000 in extreme northeastern Mississippi, since December, but local police had not had any contact with him prior to his arrest, Corinth Police Department Capt. Ralph Dance told The Associated Press on Thursday. Dance said the department aided the FBI during the arrest and that Curtis did not resist. Since Curtis arrived in the town, he had been living in "government housing," Dance said. He did not elaborate.

Police maintained a perimeter Thursday around Curtis' home, and federal investigators were expected to search the house later, said local officers on the scene who declined to be identified. Four men who appeared to be investigators were in the neighborhood to speak to neighbors. There didn't appear to be any hazardous-material crews, and no neighbors were evacuated.

The material discovered in a letter to Wicker has been confirmed through field testing and laboratory testing to contain ricin, Senate Sergeant-at-Arms Terrance Gainer said Thursday. The FBI has not yet reported the results of its own testing of materials sent to Wicker and to President Barack Obama.

"Our field tests indicate it was ricin. Our lab tests confirm it was ricin. So I don't get why others are continuing to use equivocal words about this," Gainer said.

Preliminary field tests can often show false positives for ricin. Ricin is derived from the castor plant that makes castor oil. There is no antidote, and it's deadliest when inhaled. The material sent to Wicker was not weaponized, Gainer said.

An FBI intelligence bulletin obtained by The Associated Press said the two letters were postmarked Memphis, Tenn.

A Mississippi state lawmaker, Democratic Rep. Steve Holland of Plantersville, said Wednesday night that his 80-year-old mother, Lee County Justice Court Judge Sadie Holland, received a threatening letter last week with a substance that has been sent to a lab for testing. He said this letter was also signed "K.C."

"She opened it herself" on April 11 and told Holland about it three days later, Holland said.

He said she had not been to the doctor, but he planned to take her Thursday.

"She's fine," Holland said. "She's had no symptoms."

Curtis' neighbors, who said he did not seem violent, were concerned about their safety Thursday and worried by the idea that someone was making poison in a house that sits so close to their bedrooms and front yards. The one-story, single-family home is similar to the others in the neighborhood — red brick with white trim.

A church, and a community center with an outdoor children's play area, are just steps from Curtis' house. The home also is near an area with several mailboxes for the community. But neighbors said they rarely saw him retrieve mail and didn't speak with him much.

"He was quiet. He pretty much stayed to himself," said neighbor Lacey Ross, 29.

Next-door neighbor Kayla Latch, 18, lives with her mother and her two brothers and said they were worried that toxic chemicals could be released when investigators enter the home.

Latch said Curtis lived with a woman and teenage boy when he first moved in, but they appeared to have moved out.

Kayla Latch said she slept in the living room Wednesday night.

"I'm still a little scared because my room is right next to his house," Latch said. "I didn't even sleep in my bed."

Latch's mother, Melissa Strickland, said two men who identified themselves as being with the FBI came to her house Thursday and asked about the man next door. She said they never identified Curtis by name.

"They asked me if I saw a lot of people coming and going from his house," she said. "I told them, "No."

Ricky Curtis, who said he was Kevin Curtis' cousin, said the family was shocked by the news of the arrest. He described his cousin as a "super entertainer" who impersonated Elvis and numerous other singers.

"We're all in shock. I don't think anybody had a clue that this kind of stuff was weighing on his mind," Ricky Curtis said in a telephone interview.

Ricky Curtis said his cousin had written about problems he had with a cleaning business and that he felt the government had not treated him well, but he said nobody in the family would have expected this. He said the writings were titled, "Missing Pieces."

A MySpace page for a cleaning company called The Cleaning Crew confirms that they "do windows" and has profile photo of "Kevin Curtis, Master of Impressions." A YouTube channel under the name of Kevin Curtis has dozens of videos of him performing as different famous musicians, including Elvis Presley, Buddy Holly and Kid Rock.

Multiple online posts on various websites under the name Kevin Curtis refer to the conspiracy he claimed to uncover when working at a local hospital from 1998 to 2000.

The author wrote that the conspiracy began when he "discovered a refrigerator full of dismembered body parts & organs wrapped in plastic in the morgue of the largest non-metropolitan health care organization in the United States of America."

Curtis wrote that he was trying to "expose various parties within the government, FBI, police departments" for what he believed was "a conspiracy to ruin my reputation in the community as well as an ongoing effort to break down the foundation I worked more than 20 years to build in the country music scene."

In one post, Curtis said he sent letters to Wicker and other politicians.

"I never heard a word from anyone. I even ran into Roger Wicker several different times while performing at special banquets and fundraisers in northeast, Mississippi but he seemed very nervous while speaking with me and would make a fast exit to the door when I engaged in conversation..."

Jim Waide, an attorney in Tupelo, Miss., said he was working with Curtis' family Thursday to put together a statement about the man. Waide said the family told him Curtis has been diagnosed as bipolar and was put on medication about three years ago. "It's been a real problem to keep him on his medication," Waide said in a phone interview from Tupelo.

"He has a long history of mental illness," Waide said. "When he is on his medication, he is terrific, he's nice, he's functional. When he's off his medication, that's when there's a problem."

Waide represented Curtis in a federal lawsuit he filed in August 2000 against North Mississippi Medical Center in Tupelo. Curtis claimed employment discrimination. A judge dismissed the case in July 2001. Records show it was "dismissed for failure to prosecute."

Court records show Waide got a judge's permission to withdraw as Curtis' attorney in January 2001. Waide said he withdrew from the case because Curtis didn't trust him.

"He thought I was conspiring against him," Waide said. "He thinks everybody is out to get him."

The FBI said there was no indication of a connection between the letters and the Monday bombing in Boston that killed three people and injured more than 170. The letters to Obama and Wicker were postmarked April 8, before the marathon.

CORINTH, Miss. (AP) — A Mississippi man accused of mailing letters with suspected ricin to national leaders believed he had uncovered a conspiracy to sell human body parts on the black market and claimed "various parties within the government" were trying to ruin his reputation.

Paul Kevin Curtis, 45, is charged with threatening President Barack Obama and others, according to a Thursday news release from the U.S. Department of Justice. He is scheduled to appear in federal court on the two charges later Thursday, and if convicted could face up to 15 years in prison

An FBI affidavit also released Thursday said Curtis sent three letters with suspected ricin to President Barack Obama, U.S. Sen. Roger Wicker and a Mississippi judge. The letters read:

"No one wanted to listen to me before. There are still 'Missing Pieces.' Maybe I have your attention now even if that means someone must die. This must stop. To see a wrong and not expose it, is to become a silent partner to its continuance. I am KC and I approve this message."

The affidavit says Curtis had sent letters to Wicker's office several times before with the message "this is Kevin Curtis and I approve this message."

In several letters to Wicker and other officials, Curtis said he was writing a novel about black market body parts called "Missing Pieces."

Curtis also had posted language similar to the letters on his Facebook page, the affidavit says.

The documents indicate Curtis had been distrustful of the government for years. In 2007, Curtis' ex-wife called police in Booneville, Miss., to report that her husband was extremely delusional, anti-government and felt the government was spying on him with drones.

Curtis was arrested Wednesday at his home in Corinth, near the Tennessee state line. He was being held in the Lafayette County jail in Oxford, Miss.

Curtis had been living in Corinth, a city of about 14,000 in extreme northeastern Mississippi, since December, but local police had not had any contact with him prior to his arrest, Corinth Police Department Capt. Ralph Dance told The Associated Press on Thursday. Dance said the department aided the FBI during the arrest and that Curtis did not resist. Since Curtis arrived in the town, he had been living in "government housing," Dance said. He did not elaborate.

Police maintained a perimeter Thursday around Curtis' home, and federal investigators were expected to search the house later in the morning, said local officers on the scene who declined to be identified. Four men who appeared to be investigators were in the neighborhood to speak to neighbors. There didn't appear to be any hazardous-material crews, and no neighbors were evacuated.

The material discovered in a letter to Wicker has been confirmed through field testing and laboratory testing to contain ricin, Senate Sergeant-at-Arms Terrance Gainer said Thursday. The FBI has not yet reported the results of its own testing of materials sent to Wicker and to President Barack Obama.

"Our field tests indicate it was ricin. Our lab tests confirm it was ricin. So I don't get why others are continuing to use equivocal words about this," Gainer said.

Preliminary field tests can often show false positives for ricin. Ricin is derived from the castor plant that makes castor oil. There is no antidote, and it's deadliest when inhaled. The material sent to Wicker was not weaponized, Gainer said.

An FBI intelligence bulletin obtained by The Associated Press said the two letters were postmarked Memphis, Tenn.

A Mississippi state lawmaker, Democratic Rep. Steve Holland of Plantersville, said Wednesday night that his 80-year-old mother, Lee County Justice Court Judge Sadie Holland, received a threatening letter last week with a substance that has been sent to a lab for testing. He said this letter was also signed "K.C."

"She opened it herself" on April 11 and told Holland about it three days later, Holland said.

He said she had not been to the doctor, but he planned to take her Thursday.

"She's fine," Holland said. "She's had no symptoms."

Curtis' neighbors, who said he did not seem violent, were concerned about their safety Thursday and worried by the idea that someone was making poison in a house that sits so close to their bedrooms and front yards. The one-story, single-family home is similar to the others in the neighborhood — red brick with white trim.

A church, and a community center with an outdoor children's play area, are just steps from Curtis' house. The home also is near an area with several mailboxes for the community. But neighbors said they rarely saw him retrieve mail and didn't speak with him much.

"He was quiet. He pretty much stayed to himself," said neighbor Lacey Ross, 29.

Next-door neighbor Kayla Latch, 18, lives with her mother and her two brothers and said they were worried that toxic chemicals could be released when investigators enter the home.

Latch said Curtis lived with a woman and teenage boy when he first moved in, but they appeared to have moved out.

Kayla Latch said she slept in the living room Wednesday night.

"I'm still a little scared because my room is right next to his house," Latch said. "I didn't even sleep in my bed."

Latch's mother, Melissa Strickland, two men who identified themselves as being with the FBI came to her house Thursday and asked about the man next door. She said they never identified Curtis by name.

"They asked me if I saw a lot of people coming and going from his house," she said. "I told them, "No."

Ricky Curtis, who said he was Kevin Curtis' cousin, said the family was shocked by the news of the arrest. He described his cousin as a "super entertainer" who impersonated Elvis and numerous other singers.

"We're all in shock. I don't think anybody had a clue that this kind of stuff was weighing on his mind," Ricky Curtis said in a telephone interview.

Ricky Curtis said his cousin had written about problems he had with a cleaning business and that he felt the government had not treated him well, but he said nobody in the family would have expected this. He said the writings were titled, "Missing Pieces."

A MySpace page for a cleaning company called The Cleaning Crew confirms that they "do windows" and has profile photo of "Kevin Curtis, Master of Impressions." A YouTube channel under the name of Kevin Curtis has dozens of videos of him performing as different famous musicians, including Elvis Presley, Buddy Holly and Kid Rock.

Multiple online posts on various websites under the name Kevin Curtis refer to the conspiracy he claimed to uncover when working at a local hospital from 1998 to 2000.

The author wrote that the conspiracy began when he "discovered a refrigerator full of dismembered body parts & organs wrapped in plastic in the morgue of the largest non-metropolitan health care organization in the United States of America."

Curtis wrote that he was trying to "expose various parties within the government, FBI, police departments" for what he believed was "a conspiracy to ruin my reputation in the community as well as an ongoing effort to break down the foundation I worked more than 20 years to build in the country music scene."

In one post, Curtis said he sent letters to Wicker and other politicians.

"I never heard a word from anyone. I even ran into Roger Wicker several different times while performing at special banquets and fundraisers in northeast, Mississippi but he seemed very nervous while speaking with me and would make a fast exit to the door when I engaged in conversation..."

Jim Waide, an attorney in Tupelo, Miss., said he was working with Curtis' family Thursday to put together a statement about the man. Waide said the family told him Curtis has been diagnosed as bipolar and was put on medication about three years ago. "It's been a real problem to keep him on his medication," Waide said in a phone interview from Tupelo.

"He has a long history of mental illness," Waide said. "When he is on his medication, he is terrific, he's nice, he's functional. When he's off his medication, that's when there's a problem."

Waide represented Curtis in a federal lawsuit he filed in August 2000 against North Mississippi Medical Center in Tupelo. Curtis claimed employment discrimination. A judge dismissed the case in July 2001. Records show it was "dismissed for failure to prosecute."

Court records show Waide got a judge's permission to withdraw as Curtis' attorney in January 2001. Waide said he withdrew from the case because Curtis didn't trust him.

"He thought I was conspiring against him," Waide said. "He thinks everybody is out to get him."

The FBI said there was no indication of a connection between the letters and the Monday bombing in Boston that killed three people and injured more than 170. The letters to Obama and Wicker were postmarked April 8, before the marathon.

OXFORD, Miss. (AP) — A Mississippi man charged with mailing letters with suspected ricin to national leaders was surprised by his arrest and maintains he is innocent, his attorney said Thursday after his first appearance.

Paul Kevin Curtis, 45, wore shackles and a Johnny Cash T-shirt in the federal courtroom. His handcuffs were taken off for the brief hearing, and he said little.

He faces two charges on accusations of threatening President Barack Obama and others.

He nodded his head and said, "Yes, ma'am" when the judge asked whether he understood the charges and possible penalties

He did not enter a plea on the two charges. The judge said a preliminary hearing and a detention hearing are scheduled for 3 p.m. Friday.

Attorney Christi R. McCoy said Curtis "maintains 100 percent that he did not do this."

"I know Kevin, I know his family," she said. "This is a huge shock."

McCoy said she has not yet decided whether to seek a hearing to determine if Curtis is mentally competent to stand trial.

Curtis, who was arrested Wednesday at his home in Corinth, near the Tennessee state line, was being held in the Lafayette County jail in Oxford, Miss.

An FBI affidavit says Curtis sent three letters with suspected ricin to President Barack Obama, U.S. Sen. Roger Wicker and a Mississippi judge. The letters read:

"No one wanted to listen to me before. There are still 'Missing Pieces.' Maybe I have your attention now even if that means someone must die. This must stop. To see a wrong and not expose it, is to become a silent partner to its continuance. I am KC and I approve this message."

The affidavit says Curtis had sent letters to Wicker's office several times before with the message "this is Kevin Curtis and I approve this message."

In several letters to Wicker and other officials, Curtis said he was writing a novel about black market body parts called "Missing Pieces."

Curtis also had posted language similar to the letters on his Facebook page, the affidavit says.

The documents indicate Curtis had been distrustful of the government for years. In 2007, Curtis' ex-wife called police in Booneville, Miss., to report that her husband was extremely delusional, anti-government and felt the government was spying on him with drones.

Curtis was arrested Wednesday at his home in Corinth, near the Tennessee state line. He was being held in the Lafayette County jail in Oxford, Miss.

He believed he had uncovered a conspiracy to sell human body parts on the black market and claimed "various parties within the government" were trying to ruin his reputation.

Curtis had been living in Corinth, a city of about 14,000 in extreme northeastern Mississippi, since December, but local police had not had any contact with him prior to his arrest, Corinth Police Department Capt. Ralph Dance told The Associated Press on Thursday. Dance said the department aided the FBI during the arrest and that Curtis did not resist. Since Curtis arrived in the town, he had been living in "government housing," Dance said. He did not elaborate.

Police maintained a perimeter Thursday around Curtis' home, and federal investigators were expected to search the house later, said local officers on the scene who declined to be identified. Four men who appeared to be investigators were in the neighborhood to speak to neighbors. There didn't appear to be any hazardous-material crews, and no neighbors were evacuated.

The material discovered in a letter to Wicker has been confirmed through field testing and laboratory testing to contain ricin, Senate Sergeant-at-Arms Terrance Gainer said Thursday. The FBI has not yet reported the results of its own testing of materials sent to Wicker and to President Barack Obama.

"Our field tests indicate it was ricin. Our lab tests confirm it was ricin. So I don't get why others are continuing to use equivocal words about this," Gainer said.

Preliminary field tests can often show false positives for ricin. Ricin is derived from the castor plant that makes castor oil. There is no antidote, and it's deadliest when inhaled. The material sent to Wicker was not weaponized, Gainer said.

An FBI intelligence bulletin obtained by The Associated Press said the two letters were postmarked Memphis, Tenn.

A Mississippi state lawmaker, Democratic Rep. Steve Holland of Plantersville, said Wednesday night that his 80-year-old mother, Lee County Justice Court Judge Sadie Holland, received a threatening letter last week with a substance that has been sent to a lab for testing. He said this letter was also signed "K.C."

"She opened it herself" on April 11 and told Holland about it three days later, Holland said.

He said she had not been to the doctor, but he planned to take her Thursday.

"She's fine," Holland said. "She's had no symptoms."

Curtis' neighbors, who said he did not seem violent, were concerned about their safety Thursday and worried by the idea that someone was making poison in a house that sits so close to their bedrooms and front yards. The one-story, single-family home is similar to the others in the neighborhood — red brick with white trim.

A church, and a community center with an outdoor children's play area, are just steps from Curtis' house. The home also is near an area with several mailboxes for the community. But neighbors said they rarely saw him retrieve mail and didn't speak with him much.

"He was quiet. He pretty much stayed to himself," said neighbor Lacey Ross, 29.

Next-door neighbor Kayla Latch, 18, lives with her mother and her two brothers and said they were worried that toxic chemicals could be released when investigators enter the home.

Latch said Curtis lived with a woman and teenage boy when he first moved in, but they appeared to have moved out.

Kayla Latch said she slept in the living room Wednesday night.

"I'm still a little scared because my room is right next to his house," Latch said. "I didn't even sleep in my bed."

Latch's mother, Melissa Strickland, said two men who identified themselves as being with the FBI came to her house Thursday and asked about the man next door. She said they never identified Curtis by name.

"They asked me if I saw a lot of people coming and going from his house," she said. "I told them, "No."

Ricky Curtis, who said he was Kevin Curtis' cousin, said the family was shocked by the news of the arrest. He described his cousin as a "super entertainer" who impersonated Elvis and numerous other singers.

"We're all in shock. I don't think anybody had a clue that this kind of stuff was weighing on his mind," Ricky Curtis said in a telephone interview.

Ricky Curtis said his cousin had written about problems he had with a cleaning business and that he felt the government had not treated him well, but he said nobody in the family would have expected this. He said the writings were titled, "Missing Pieces."

A MySpace page for a cleaning company called The Cleaning Crew confirms that they "do windows" and has profile photo of "Kevin Curtis, Master of Impressions." A YouTube channel under the name of Kevin Curtis has dozens of videos of him performing as different famous musicians, including Elvis Presley, Buddy Holly and Kid Rock.

Multiple online posts on various websites under the name Kevin Curtis refer to the conspiracy he claimed to uncover when working at a local hospital from 1998 to 2000.

The author wrote that the conspiracy began when he "discovered a refrigerator full of dismembered body parts & organs wrapped in plastic in the morgue of the largest non-metropolitan health care organization in the United States of America."

Curtis wrote that he was trying to "expose various parties within the government, FBI, police departments" for what he believed was "a conspiracy to ruin my reputation in the community as well as an ongoing effort to break down the foundation I worked more than 20 years to build in the country music scene."

In one post, Curtis said he sent letters to Wicker and other politicians.

"I never heard a word from anyone. I even ran into Roger Wicker several different times while performing at special banquets and fundraisers in northeast, Mississippi but he seemed very nervous while speaking with me and would make a fast exit to the door when I engaged in conversation..."

Jim Waide, an attorney in Tupelo, Miss., said he was working with Curtis' family Thursday to put together a statement about the man. Waide said the family told him Curtis has been diagnosed as bipolar and was put on medication about three years ago. "It's been a real problem to keep him on his medication," Waide said in a phone interview from Tupelo.

"He has a long history of mental illness," Waide said. "When he is on his medication, he is terrific, he's nice, he's functional. When he's off his medication, that's when there's a problem."

Waide represented Curtis in a federal lawsuit he filed in August 2000 against North Mississippi Medical Center in Tupelo. Curtis claimed employment discrimination. A judge dismissed the case in July 2001. Records show it was "dismissed for failure to prosecute."

Court records show Waide got a judge's permission to withdraw as Curtis' attorney in January 2001. Waide said he withdrew from the case because Curtis didn't trust him.

"He thought I was conspiring against him," Waide said. "He thinks everybody is out to get him."

The FBI said there was no indication of a connection between the letters and the Monday bombing in Boston that killed three people and injured more than 170. The letters to Obama and Wicker were postmarked April 8, before the marathon.

CORINTH, Miss. (AP) — A Mississippi man accused of mailing letters with suspected ricin to national leaders believed he had uncovered a conspiracy to sell human body parts on the black market and claimed "various parties within the government" were trying to ruin his reputation.

Paul Kevin Curtis, 45, is charged with threatening President Barack Obama and others, according to a Thursday news release from the U.S. Department of Justice. He is scheduled to appear in federal court on the two charges later Thursday, and if convicted could face up to 15 years in prison

An FBI affidavit also released Thursday said Curtis sent three letters with suspected ricin to President Barack Obama, U.S. Sen. Roger Wicker and a Mississippi judge. The letters read:

"No one wanted to listen to me before. There are still 'Missing Pieces.' Maybe I have your attention now even if that means someone must die. This must stop. To see a wrong and not expose it, is to become a silent partner to its continuance. I am KC and I approve this message."

The affidavit says Curtis had sent letters to Wicker's office several times before with the message "this is Kevin Curtis and I approve this message."

In several letters to Wicker and other officials, Curtis said he was writing a novel about black market body parts called "Missing Pieces."

Curtis also had posted language similar to the letters on his Facebook page, the affidavit says.

The documents indicate Curtis had been distrustful of the government for years. In 2007, Curtis' ex-wife called police in Booneville, Miss., to report that her husband was extremely delusional, anti-government and felt the government was spying on him with drones.

Curtis was arrested Wednesday at his home in Corinth, near the Tennessee state line. He was being held in the Lafayette County jail in Oxford, Miss.

Curtis had been living in Corinth, a city of about 14,000 in extreme northeastern Mississippi, since December, but local police had not had any contact with him prior to his arrest, Corinth Police Department Capt. Ralph Dance told The Associated Press on Thursday. Dance said the department aided the FBI during the arrest and that Curtis did not resist. Since Curtis arrived in the town, he had been living in "government housing," Dance said. He did not elaborate.

Police maintained a perimeter Thursday around Curtis' home, and federal investigators were expected to search the house later in the morning, said local officers on the scene who declined to be identified. Four men who appeared to be investigators were in the neighborhood to speak to neighbors. There didn't appear to be any hazardous-material crews, and no neighbors were evacuated.

The material discovered in a letter to Wicker has been confirmed through field testing and laboratory testing to contain ricin, Senate Sergeant-at-Arms Terrance Gainer said Thursday. The FBI has not yet reported the results of its own testing of materials sent to Wicker and to President Barack Obama.

"Our field tests indicate it was ricin. Our lab tests confirm it was ricin. So I don't get why others are continuing to use equivocal words about this," Gainer said.

Preliminary field tests can often show false positives for ricin. Ricin is derived from the castor plant that makes castor oil. There is no antidote, and it's deadliest when inhaled. The material sent to Wicker was not weaponized, Gainer said.

An FBI intelligence bulletin obtained by The Associated Press said the two letters were postmarked Memphis, Tenn.

A Mississippi state lawmaker, Democratic Rep. Steve Holland of Plantersville, said Wednesday night that his 80-year-old mother, Lee County Justice Court Judge Sadie Holland, received a threatening letter last week with a substance that has been sent to a lab for testing. He said this letter was also signed "K.C."

"She opened it herself" on April 11 and told Holland about it three days later, Holland said.

He said she had not been to the doctor, but he planned to take her Thursday.

"She's fine," Holland said. "She's had no symptoms."

Curtis' neighbors, who said he did not seem violent, were concerned about their safety Thursday and worried by the idea that someone was making poison in a house that sits so close to their bedrooms and front yards. The one-story, single-family home is similar to the others in the neighborhood — red brick with white trim.

A church, and a community center with an outdoor children's play area, are just steps from Curtis' house. The home also is near an area with several mailboxes for the community. But neighbors said they rarely saw him retrieve mail and didn't speak with him much.

"He was quiet. He pretty much stayed to himself," said neighbor Lacey Ross, 29.

Next-door neighbor Kayla Latch, 18, lives with her mother and her two brothers and said they were worried that toxic chemicals could be released when investigators enter the home.

Latch said Curtis lived with a woman and teenage boy when he first moved in, but they appeared to have moved out.

Kayla Latch said she slept in the living room Wednesday night.

"I'm still a little scared because my room is right next to his house," Latch said. "I didn't even sleep in my bed."

Latch's mother, Melissa Strickland, two men who identified themselves as being with the FBI came to her house Thursday and asked about the man next door. She said they never identified Curtis by name.

"They asked me if I saw a lot of people coming and going from his house," she said. "I told them, "No."

Ricky Curtis, who said he was Kevin Curtis' cousin, said the family was shocked by the news of the arrest. He described his cousin as a "super entertainer" who impersonated Elvis and numerous other singers.

"We're all in shock. I don't think anybody had a clue that this kind of stuff was weighing on his mind," Ricky Curtis said in a telephone interview.

Ricky Curtis said his cousin had written about problems he had with a cleaning business and that he felt the government had not treated him well, but he said nobody in the family would have expected this. He said the writings were titled, "Missing Pieces."

A MySpace page for a cleaning company called The Cleaning Crew confirms that they "do windows" and has profile photo of "Kevin Curtis, Master of Impressions." A YouTube channel under the name of Kevin Curtis has dozens of videos of him performing as different famous musicians, including Elvis Presley, Buddy Holly and Kid Rock.

Multiple online posts on various websites under the name Kevin Curtis refer to the conspiracy he claimed to uncover when working at a local hospital from 1998 to 2000.

The author wrote that the conspiracy began when he "discovered a refrigerator full of dismembered body parts & organs wrapped in plastic in the morgue of the largest non-metropolitan health care organization in the United States of America."

Curtis wrote that he was trying to "expose various parties within the government, FBI, police departments" for what he believed was "a conspiracy to ruin my reputation in the community as well as an ongoing effort to break down the foundation I worked more than 20 years to build in the country music scene."

In one post, Curtis said he sent letters to Wicker and other politicians.

"I never heard a word from anyone. I even ran into Roger Wicker several different times while performing at special banquets and fundraisers in northeast, Mississippi but he seemed very nervous while speaking with me and would make a fast exit to the door when I engaged in conversation..."

Jim Waide, an attorney in Tupelo, Miss., said he was working with Curtis' family Thursday to put together a statement about the man. Waide said the family told him Curtis has been diagnosed as bipolar and was put on medication about three years ago. "It's been a real problem to keep him on his medication," Waide said in a phone interview from Tupelo.

"He has a long history of mental illness," Waide said. "When he is on his medication, he is terrific, he's nice, he's functional. When he's off his medication, that's when there's a problem."

Waide represented Curtis in a federal lawsuit he filed in August 2000 against North Mississippi Medical Center in Tupelo. Curtis claimed employment discrimination. A judge dismissed the case in July 2001. Records show it was "dismissed for failure to prosecute."

Court records show Waide got a judge's permission to withdraw as Curtis' attorney in January 2001. Waide said he withdrew from the case because Curtis didn't trust him.

"He thought I was conspiring against him," Waide said. "He thinks everybody is out to get him."

The FBI said there was no indication of a connection between the letters and the Monday bombing in Boston that killed three people and injured more than 170. The letters to Obama and Wicker were postmarked April 8, before the marathon.